Perforated capsule filter

ABSTRACT

The present invention is a capsule that has a perforated outer shell that is substantially filled with a filtering media which has been pressurized to remove air pockets resulting in more effective and consistent filtration. The media may be activated carbon or other filtering media and may include other flavorants, aromatic substances, or a combination thereof. The present invention, thus, also provides an insert for a smoking article. The insert is the capsule of the present invention, namely, a perforated shell with media filling the cavity (without “air pockets”) formed by the shell. The capsule is placed within the smoking article at a point between the tobacco and the point of inhalation (the mouthpiece) such that, upon inhalation, the tobacco smoke is drawn completely and consistently through the media. Alternatively, the capsule may be integrated into a cigarette holder, pipe, or the like at a point in-line between the tobacco charge and the smoker.

This is a continuation-in-part application of pending application Ser. No. 10/608650.

FIELD OF THE INVENTION

The present invention generally relates to a filter, and more particularly relates to an improved filter for smoking articles, such as cigarettes.

BACKGROUND OF THE INVENTION

Several filter designs exist for smoking articles, such as cigarettes, cigars, and similar articles. Such filters traditionally are formed with different types of filtering media to reduce or eliminate undesirable components from inhalation by the smoker. Fibrous filters, such as cellulose acetate or paper commonly are used as filter media for tobacco smoke. In addition, activated carbon is used in conjunction with the fibrous filter to absorb certain tobacco smoke combustion by-products. As used herein, “activated carbon” or “carbon” refers to charcoal that is treated to result in a highly porous, highly absorbent filter media. Thus, generally, a smoking article may contain a charge of tobacco, a fibrous filter, and a metered amount of activated carbon.

While carbon plays an important role in the filtering process, the location of the carbon in the smoking article can lead to less than preferred results. The carbon typically is placed within the smoking article in an area within the fibrous filter during the assembly process. For example, the filter section of a cigarette can comprise a first fibrous filter, an amount of activated carbon, and a second fibrous filter. In this manner, the activated charcoal is intended to serve as an additional filter media through which the tobacco smoke must pass during suction by the smoker.

Unfortunately, because of limitations in filling the carbon cavity (without air pockets) through traditional gravitational fill methods air pockets are left in the carbon media. Also during movement of the cigarettes during the cigarette manufacturing process or the cigarette distribution process, the activated charcoal in the filter tends to settle in the cavity leaving air pockets in the filter. Thus, the smoker does not likely draw the tobacco smoke through the activated charcoal media consistently, and the flavor of the cigarette may vary depending on the position of the cigarette when the smoker holds it and commences inhalation. For example, if the smoker is reclining in a lawn chair at the beach, gravity will cause the carbon to fall back towards the mouthpiece of the cigarette, maximizing the filtration potential of the filter medium by eliminating the path of least resistance. If that same smoker is driving with another cigarette (from the same pack) in his or her mouth, the holding plane of the cigarette is parallel to the earth. The carbon now settles to a position creating a void across the top of the cigarette cylinder filter cavity. In this position that same smoker, smoking a cigarette from the same pack would be afforded the lowest effective filtration and a significant change in flavor from the cigarette smoked ten minutes earlier while reclining in the beach chair. Thus the smoker may consider the cigarette of low quality as one cigarette flavor may vary from another in the same package. This results from the different paths the smoke may take through the carbon and other times completely bypassing it. The result is a significant variation in the filtration the smoker receives based upon the position of the cigarette during inhalation. The smoker will experience this variation in the cigarette's taste and flavor. Inconsistent taste and bad taste are among the top 10 consumer complaints to tobacco companies from customers.

Under the current filter manufacturing process, tobacco smoke may take the path of least resistance and avoid the activated charcoal. Thus, current methods for using fibrous and carbon filter media do not make consistent or efficient use of the activated carbon media and also contribute to an inconsistent flavor as perceived by the smoker which causes the smoker to experience poor filtration (placing the smoker at greater risk, to experience different flavors, and to perceive inconsistent quality of the cigarette thereby resulting in reduced brand loyalty). Brand loyalty in the cigarette industry represents a significant financial impact, as each percent of the United States cigarette market represents approximately $1,000,000,000.00 in sales.

Another current deficiency in the use of activated charcoal is migration of the charcoal into the fibrous filter media. Most notably, black discoloration of the fibrous filter media can occur as the carbon rests against the fibrous filter or migrates back towards the mouthpiece. Potentially, a smoker may open a new pack of cigarettes and find at least one cigarette discolored by the migration of the carbon through the fibrous materials. This discoloration is very apparent as the carbon is black and the filter is white. This can lead to another form of consumer complaint and dissatisfaction—perceived lower product quality.

There is a need, therefore, for an improved filtration application that overcomes the deficiencies of inefficient carbon filtration, inconsistent flavor as a result of air pocket in the carbon filtration media, and undesirable migration because the carbon is not being contained.

SUMMARY

The present invention overcomes the deficiencies of the prior art by providing a capsule that has a perforated outer shell that is substantially filled with the filtering media substantially without air pockets. The media may be carbon or other filtering media. Additionally, other flavorants or aromatic substances may be included to impart a specific taste or modify the smell of the tobacco smoke. Thus, the media within the capsule may be filtration media, taste-modifying media, aromatic media, or a combination thereof.

The present invention also provides an insert for a smoking article. The insert is the capsule of the present invention; namely, a perforated shell with media substantially filling the cavity formed by the shell substantially. The media is compressed by tamping to remove air pockets just prior to insertion in the shell. The capsule is placed within the smoking article at a point between the tobacco and the point of inhalation (the mouthpiece) such that, upon inhalation, the tobacco smoke is drawn consistently and completely through the filter media. The capsule may be so placed either during manufacture of the smoking article, or as part of an after-purchase smoking accessory such as a cigarette holder or the like.

More broadly, the present invention also provides a filter for any in-line application between a polluted source and a substantially pollutant-free product. The filter is the capsule of the present invention; namely, a perforated shell with media substantially air pocket free filtering media substantially filling the cavity formed by the shell. The capsule is placed at an effective point between the source and the product, and the media substantially filters the contaminant as the material flows through the perforated, media-filled capsule.

These and other aspects of the present invention as disclosed herein will become apparent to those skilled in the art after a reading of the following description of the preferred embodiments.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic plan view of an automated process for producing perforated capsule filters.

FIG. 2 a is a cross-sectional view of a smoking article including an embodiment of the apparatus of the present invention.

FIG. 2 b is a cross-sectional view of a smoking article including another embodiment of the apparatus of the present invention.

FIG. 3 is an elevation view of an embodiment of the present invention with a partial cut-away portion.

FIG. 4 is a perforation pattern for a perforated capsule.

FIG. 5 is a side elevational, sectional and slightly separated view of the upper and lower segment blocks showing the upwardly extending individual capsule holding recess forming a bump on the lower segment block and the contoured bump-receiving portion on the upper segment block for cooperatively receiving the lower segment bump block to prevent the escape of media when the top and bottom shell portions are closed as air pockets are expelled through the perforations in the outer shell.

FIG. 6 is a perspective view of the top of the upper segment block of the present invention.

FIG. 7 is a perspective view of the bottom of the upper segment block shown in FIG. 6 having the bump-receiving portion configured therein.

FIG. 8 is a perspective view of the top of the lower segment block showing the upwardly extending individual cap holding recesses forming bumps.

FIG. 9 is a perspective view of the bottom of the lower segment block shown in FIG. 8.

FIG. 10 is a perspective view of the top and bottom segment blocks in the closed position.

FIG. 11 is another perspective view of the top and bottom segment blocks in the closed position.

DETAILED DESCRIPTION

As illustrated in FIG. 1, one preferred method for forming the capsules of the present invention involves the modification of any standard hard capsule filling and closing machine 80, such as the Bosch GKF 400, GKF 700, GKF 1200, GKF 1500, GKF 2000, GKF 2500, GKF 3000, distributed by Bosch Group of TL Systems Corporation of Minneapolis, Minn. While any filling and closing machine may be used, as shown in FIG. 1, the machine 80 may include a turntable 20 which rotates among a plurality of process stations 1-12. One or more discrete process steps may be performed at each station 1-12. In the embodiment shown in FIG. 1, empty non-perforated capsules 40 are delivered to the turntable 20 at station 1, and the capsules 40 are straightened and aligned for subsequent processing. Next, the capsules 40 are passed to station 2 for perforation of the ends of the capsules 40 by laser 30. Laser 30 may include a control unit 32 and a remote head 34. Laser light is directed from the remote head 34 to perforate the capsules 40. Preferably, both ends of the capsule shells 40 are perforated simultaneously, i.e. by passing beams of laser light through one end of the capsule shell 40, and out through the opposite end of the shell 40. Alternatively, the shell halves 50, 60 may be separated prior to perforation, and each half 50, 60 may be perforated individually.

Any appropriate apparatus may be used to perforate the capsules, however, laser perforation is preferred for accuracy in placement and perforation size. One example of a laser that may be used for laser perforation is the Blazer 5000 or 6000 available from Lasertechnics® Inc. of Albuquerque, N.M. The capsules are perforated by directing a laser at the desired portion of the capsule. Laser beam strength and duration are selected to cause complete perforation through the top and bottom of the capsule with desired locations and perforation diameters. Suitable diameters include, but are not limited to, about 0.05 mm to about 1.0 mm. Perforation size must be small enough to minimize escaping carbon or other media from within the capsule, but large enough to allow for the smoker to effectively draw air through the perforated, media-filled capsule. Further, preferably the perforations make up approximately 45% of each of the top and bottom end surface areas of the capsule. The perforations may make up more or less of the end surface areas of the capsule depending on the desired resistance to air flow through the capsule and/or the required size of webs or ligaments between the perforations necessary to maintain the structural integrity of the capsule.

Lasers have become increasingly common in consumer product manufacturing. For example, lasers are currently used to provide date codes on cartons and packages for consumer goods by selectively burning away ink from package surfaces with directed laser light. By burning away the surface color with the laser in this way, a mark is established due to the resulting contrast between the adjacent colored and non-colored portions of the package surfaces. Also, laser light may be passed through a mask or template such that a desired pattern of laser light impinges on a target surface. The portions of the laser light which pass through the mask or template burn away those portions of a surface color on the target surface which are exposed to the light, thereby establishing a desired contrasting image on the target surface.

Such lasers may also be used to produce a perforated capsule according to the present invention. The power or intensity of the laser light applied to a capsule surface is selected so that it is sufficient to burn through the upper and lower portions of the capsule when the capsule is empty. A template or mask having a desired hole pattern is used to selectively direct portions of the laser light onto the capsule surface. The hole pattern may include a variety of hole sizes and hole locations. The pattern should, however, leave sufficient webs or ligaments between adjacent perforations so that the structural integrity of the perforated upper and lower portions of the capsule are maintained, while providing perforations which are sufficient to permit air to be adequately drawn through the capsule.

One perforation pattern which can be used in the present invention is illustrated in FIG. 3 and FIG. 4. In a preferred arrangement, the perforation pattern includes about 124 holes having diameters of about 0.25 mm, and about seventy-six (76) larger holes having diameters of about 0.5 mm. This combination of perforations provides openings in about 45 percent of the surface area of the perforated regions of the capsule to permit gas flow therethrough. Tests may be performed to determine the optimum number of perforations, perforation diameters, perforation locations, perforation patterns, perforation shapes, etc. that will provide sufficient structural integrity of a capsule while also permitting adequate gas flow through the capsule for a particular application.

Alternatively, the capsules may be perforated as the capsules are originally produced. For example, foaming agents may be added to the capsule shell material during formation of the capsules. As the capsule shells harden, the foaming agents leave behind voids or open cells in the thin capsule walls. By controlling the concentration of the foaming agent in the shell material, capsules having perforated walls with a desired permeability are produced. Such capsules eliminate the need to form a perforated hole pattern in the capsules using a laser or the like, thereby reducing filter production costs. Methods for using foaming agents to form open cells in a thin-walled material or membrane are disclosed in U.S. Pat. No. 5,853,633, which is hereby incorporated by reference in its entirety. The use of foaming agents to form open cells in other types of materials is disclosed in U.S. Pat. Nos. 4,800,214; 5,084,101; and 5,242,635. When such pre-perforated capsules are used, station 2 in FIG. 1 can be eliminated.

Referring again to FIG. 1, the perforated capsules 40 are separated into bottom capsule portions 60 and capsule caps 50 at station 3. The caps 50 may then be moved aside at station 4 to permit subsequent vertical filling of the bottoms 60. The bottoms 60 are then advanced to a dosing station 5. The dosing station 5 deposits fill material into the capsule bottoms 60. The composition of the fill material is discussed in more detail below. Preferably, dosing station 5 includes a tamping apparatus to reduce the risk of inaccurate fill weights and assure that no air pockets exist in the filled carbon. This method of providing a small tamp to the carbon prior to its transfer into the capsule will (a) remove any voids or air pockets in the carbon and (b) compress the carbon media prior to placing it in the perforated capsule. Once the carbon is placed in the perforated capsule, the perforated capsule is then immediately closed, the memory of the carbon will then allow it to expand and actually place an internal physical pressure inside the perforated capsule thereby assuring that during handling, shipping and distribution of the cigarette, the voids will not settle into the carbon and create air pockets. Then, optionally, the bottom halves 60 may be subjected to further dosing at one or more subsequent dosing stations 6. The further dosing process may include dosing with other dosing materials that provide desired benefits such as flavor enhancers or the like. As discussed below, the capsules may contain a variety of fill materials.

After dosing, the capsule halves 50, 60 advance to an inspection apparatus at station 7 that ejects any defective capsule portions 50, 60. Then, the caps 50 and dosed bottoms 60 are realigned at station 8, assembled together at station 9, and closed at station 10. Thereafter, the filled and closed capsules 100 are discharged, and optionally sampled, by discharge apparatus 11. The recesses in turntable 20 are then cleaned using a cleaning device at station 12 as is known in the art. The cycle is then repeated to produce more perforated capsules 100.

An alternative embodiment for removing air pockets from the capsule-filling media has been developed. In the present machine structure, the encapsulator opens the empty capsules with the bottom or lower part of the capsule 120 landing in the lower segment block 122 and the and the cap or upper portion of the capsule 124 landing in the upper segment block 126. The bottom part of the capsule 120 is then provided with charcoal or other appropriate media at the dosing station.

Lower closing pins (not shown) push the bottom of the capsule 120 out of the lower segment block 122 and up into the upper segment block 126 while the upper closing arm holds the capsule in place. This causes the capsule body 120 to enter the capsule cap 124 and continue to its closed (snapped) position. If the placement of additional filter media in the bottom is attempted just before the capsule is closed, it overflows during the closing operation and frequently spills out of the 0.5 mm gap normally existing between the lower segment block and the upper segment block thus not likely providing enough media to remove all air pockets within the closed capsule and otherwise contaminating the working area.

To eliminate this problem, the lower segment block is shaped so that the individual capsule bottom holding recesses 130 each extend upwardly and away from the lower segment block 122 to form a small bump 132 as shown in FIG. 5. The upper segment bottom surface is designed so that a mating recess 134 cooperatively receives each upwardly extending capsule bottom holding recess bump 132, the two nest together, and all media placed in the capsule bottom is captured within the capsule when it is closed because there is no longer a 0.5 mm gap existing between the upper and lower segment blocks. Since the capsule top and bottom have perforations, any air within the enclosed media is expelled through these perforations during the closing operation. Thus the capsule bottoms can be overfilled by a predetermined amount 136 and the capsule bottoms and tops closed with the closed capsule being completely filled with media without any air pockets.

A filled and perforated capsule 100 is illustrated in FIG. 3. As shown, the capsule 100 has an outer shell 102 that defines a cavity 104. Within cavity 104, capsule 100 maintains fill material 106. The fill material 106 may be any material or combination of materials through which the polluted substance, e.g. tobacco smoke, is to be filtered or treated. Thus, for filtration or treatment of tobacco smoke, the fill material may be activated carbon or any other appropriate filtration material. The fill material or charcoal granule size is preferably larger than 0.43 mm (0.017″) and smaller than 0.99 mm (0.039″). An additional fill material may be the sodium salt of 2-mercaptoethane-sulphonic acid, also known as mesna, as described in U.S. Pat. No. 4,532,947. The filter material may be chosen to remove undesirable components such as tars, nicotine, volatiles, mutagens, carcinogens, saturated and unsaturated aliphatic aldehydes, polycylcic aromatic hydrocarbons, nitrosamines, combinations thereof, or the like. Further, the fill material may include a flavorant or aromatic substance to impart a desired flavor or aroma to the smoker. Additionally, combinations of filtering media, flavor-modifying media, and/or aromatic-modifying media may be included as fill material 106. One preferred combination for fill material 106 is activated carbon filtering media and menthol flavorant.

The capsule shell 102 may be formed of any appropriate materials, including but not limited to gelatin, polysaccharides (such as carrageenan), or a combination thereof. Another material that may be used to form the capsule shell is Hydroxypropyl methylcellulose or another cellulosic material. The shell 102 preferably is approximately 8 mm in diameter and approximately 3 to 12 mm in length. Thus, the capsule shell 102 may be oblong or cylindrical, for example as illustrated in FIG. 2 a, or substantially circular, for example as illustrated in FIG. 2 b. Although the size of the capsule may be formed appropriately for the desired amount of carbon filtration media 106, preferably the capsule shell 102 is formed to maintain therein about 200 mg to about 300 mg of carbon fill material 106, and most preferably about 250 mg of carbon fill material.

As illustrated in FIGS. 2 a and 2 b, as an insert for a smoking article, the capsule 100 is placed within the smoking article 110 at a point between the tobacco 104 and the point of inhalation 108. As used herein, the term “smoking article” shall include a cigarette, cigarette holder, pipe, cigar, or any other article that operates to hold a burning product and facilitates inhalation of at least a portion of the combustion products. Preferably, as shown in FIG. 2 b, the smoking article 110 includes a mouthpiece section 112 having a filter 107, made from cellulosic materials. Most preferably, the capsule 100 is placed within the mouthpiece 112 between two cellulosic filters 107, as shown in FIG. 2 a. Alternatively, the capsule 100 may be integrated into the stem of a pipe in order to filter pipe smoke as it travels through the pipe stem (not shown). Still further, the capsule 100 may be integrated into a cigarette holder to filter smoke drawn from a conventional cigarette prior to inhalation by the smoker.

As will be appreciated by those skilled in the art, the capsule filter 100 of the present invention is equally useful as a filter for any in-line filtration application between a polluted source and a substantially pollutant-free product. Thus, the capsule 100 should be placed at an effective point between the source and the product point. The media substantially filters the pollutant as the pollutant flows through the perforated, media-filled capsule 100. Thus, although the preferred embodiment describes a filter 100 wherein the polluted source is a tobacco charge 104 to be smoked and the media is tobacco smoke-filtering media 106, the capsule 100 may be used for other applications. The filter 100 may be used as a portion of an after-market accessory filtration device which is configured to receive a conventional cigarette. Although specific embodiments of the present invention have been illustrated and described in detail, it is to be expressly understood that the invention is not limited thereto. The above detailed description of the embodiment is provided for example only and should not be construed as constituting any limitation of the invention. Thus, modifications will be obvious to those skilled in the art, and all modifications that do not depart from the spirit of the invention are intended to be included within the scope of the appended claims. 

1. A capsule for use as a filter for a smoking article comprising: an outer shell that defines a cavity; a plurality of perforations through at least a portion of the outer shell; and a filter media substantially filling the cavity and tamped to eliminate air pockets; wherein the outer shell is configured to be received within the smoking article.
 2. The capsule of claim 1 wherein the outer shell is comprised of gelatin, polysaccharide, hydroxypropyl methylcellulose, a cellulosic material, or a combination thereof.
 3. The capsule of claim 1 wherein the perforations are individually of such a diameter that a substantial portion of the filter media cannot readily pass therethrough.
 4. The capsule of claim 1 wherein the media is carbon.
 5. The capsule of claim 1 wherein the media is a flavor-modifier or aroma-modifier.
 6. The capsule of claim 1 wherein the outer shell is oblong.
 7. The capsule of claim 6 wherein the oblong outer shell has a diameter of approximately 8 mm and a length between about 3 mm and about 12 mm.
 8. The capsule of claim 7 wherein the oblong outer shell is substantially filled with about 200 mg to about 300 mg of substantially air pocket free carbon.
 9. The capsule of claim 1 wherein the outer shell is circular.
 10. The capsule of claim 9 having a diameter of approximately 8 mm.
 11. The capsule of claim 1 wherein the perforations are about 0.05 mm to about 1.0 mm in diameter.
 12. The capsule of claim 1 wherein the capsule includes ends having end surface areas, and the perforations comprise approximately 45 percent of the end surface areas of the capsule.
 13. In a machine for filling and closing two-piece capsules formed as an outer shell with each capsule piece having a plurality of perforations, the machine of the type on which a plurality of segment blocks are secured to a movable table and are circumferentially movable to different stations, the segment blocks including a lower segment block and an upper segment block each designed to hold separate capsule parts and movable against and away from each other, the improvement comprising: the lower segment block having individual capsule holding recesses each of which extend upwardly away from the lower segment block and, when filled with media form a bump and the upper segment block contoured to cooperatively receive each of the upwardly extending media bumps wherein the upper and lower segment blocks nest and prevent the escape of media as the air pockets are expelled through the perforations in the capsule pieces.
 14. An insert for a smoking article, the smoking article having tobacco and a first end, the insert comprising: (a) an outer shell that defines a cavity; (b) a plurality of perforations through the outer shell; and (c) a media substantially filling the cavity and tamped to eliminate air pockets, wherein the insert is placed within the smoking article at a point between the tobacco and the first end.
 15. The insert of claim 13 wherein the media is tobacco smoke-filtering media.
 16. The insert of claim 14 wherein the media is activated carbon.
 17. The insert of claim 13 wherein the media is flavor-modifying media.
 18. The insert of claim 16 wherein the flavor-modifying media is menthol.
 19. The insert of claim 13 wherein the media is aromatic-modifying media.
 20. The insert of claim 13 wherein the media is a combination of tobacco smoke-filtering and flavor-modifying media.
 21. The insert of claim 13 wherein the capsule shell is comprised of gelatin, polysaccharide, hydroxypropyl methylcellulose, a cellulosic material, or a combination thereof.
 22. The insert of claim 13 wherein the perforations are individually of such a diameter that the media cannot readily pass therethrough.
 23. The insert of claim 13 wherein the smoking article is a cigarette.
 24. The insert of claim 22 wherein the cigarette further comprises a mouthpiece having a filter and a tobacco charge, whereby the insert is placed between the tobacco charge and the mouthpiece filter.
 25. A cigarette comprising: (a) a tobacco charge; and (b) a filter, the filter further comprising: (i) an outer shell that defines a cavity; (ii) a plurality of perforations through the outer shell; and (iii) a tobacco-smoke filtering media tamped to eliminate air pockets and deposited in and substantially filling the cavity, wherein the filter is placed at an effective location to the tobacco charge for the filtration of tobacco smoke through the media.
 26. The filter of claim 24 wherein the media is capable of filtering undesired components selected from the group consisting of tars, nicotine, volatiles, mutagens, carcinogens, saturated and unsaturated aliphatic aldehydes, polycylcic aromatic hydrocarbons, and nitrosamines.
 27. A method for manufacturing a filter comprising: (a) feeding and aligning empty capsule shells; (b) perforating the shells to form a gas flow path through each shell; (c) separating the empty capsule shells into shell halves (d) dosing the shell halves with filtering media; (e) pressurizing the filtering media to remove air pockets while reassembling the shell halves to form a perforated air pocket-free media-filled capsule filter. (f) reassembling the shell halves to form a perforated, media-filled capsule filter.
 28. The method of claim 27 wherein perforating the shells comprises forming openings in the shells with a laser.
 29. The method of claim 27 wherein the capsule shells include opposed ends having end surface areas, and perforating the shells is completed over approximately 45% of the end surface areas of the shells.
 30. The method of claim 2 further comprising dosing the shell halves with an aromatic media or flavor-modifying media.
 31. A method for manufacturing a filter comprising: (a) forming capsule shell halves from a shell material comprising a foaming agent, the formed capsule shell halves having pluralities of open-cell perforations therethrough; (b) feeding and aligning empty capsule shell halves; (c) dosing the shell halves with a filtering media; (d) pressurizing the filtering media to remove air pockets while assembling the shell halves to form a perforated, media-filled capsule free of air pockets.
 32. The method of claim 31 further comprising dosing the shell halves with an aromatic media or flavor-modifying media. 